The Blindfold Was Crucial

Sissy had been apprehensive when her wife told her they were finally going to share a man.  That sissy's practice sucking cock on the dildo was now going to be put into real life use.  To help ease sissy's anxiety, her wife told her she could wear the blindfold, so she wouldn't be forced, yet, to look into the eyes of the man she was fluffing to fuck her wife.  I wonder how sissy would feel if she knew that the blindfold also concealed from her that the cock she was sucking - the cock she was getting hard and ready to fuck her wife - was the cock of her younger brother?